Introduction:
'Culture Shock', my Percy Jackson Fanfic, was about an Aztec Demigod going to Camp Half Blood. There were many references to Aztec gods, goddesses, and monsters that went unaddressed. That's what this is for. For those who don't know what culture I'm talking about think of Apocalypto by Mel Gibson, the tribe that was infamous for human sacrifices. There was a lot more stuff that went into their culture. But that's another story.
First of all, let it be known that the Aztecs were never called "Aztecs" in their time. They were known as the Mexica tribe. The various tribes of Central Mexico were generally known as the Nahua (NAH-wha) and their language was Nahuatl (na-WHA-tull) meaning "Clear Speech." Much of their culture was adopted by the surrounding tribes they conquered like Toltec and Mayan influences, then filtered through their own values.

Monsters:
The Ahuitzotl, (ah-weet-SAW-tull) is an otter-dog-monkey water monster that had a hand on its tail and let out a cry like a child, to lure people to the water, whereupon it would drown them and eat their eyes, toenails, and fingernails.

Cihuateteo, the spirits of human women who died in childbirth. Childbirth was considered a form of battle, and its victims were honored as fallen warriors. Their physical remains were thought to strengthen soldiers in battle while their spirits became the much-feared Cihuateteo who accompanied the setting sun in the west. They also haunted crossroads at night, stealing children and causing sickness, especially seizures and madness, and seducing men to sexual misbehavior. They are depicted with skeletal faces and with eagle claws for hands.

Cipatli, An enormous crocodilian monster that lived in the primordial waters before Quetzalcoatl and Tezcatlipoca teamed up to slay it and make the world from its corpse. Essentially a hybrid between a crocodile, a toad, and a shark, with mouths at every joint.

The Night Axe, a wandering monster resembling a large headless corpse with its chest and belly slit open. Its wound would open and close periodically with a sound like an axe chopping wood. If you came across it while walking at night, you were supposed to approach it fearlessly and, timing it correctly, thrust your hand into the open wound and tear out its heart. If you did this, it would grant you a wish. If you ran away, you would die miserably. Tecum's wish was to become a stronger warrior, so he was granted the ability to heal by drinking his enemies' blood, and being able to interact with Tenoch.

The Tzitzimeme (plural Tzizimimeh; couldn't find pronunciation.) , star goddesses said to harrow the world during a solar eclipse. They're beautiful women with skeletal faces and rattlesnakes for penises. Yes, they're distinctly female, and they have rattlesnakes for dicks.

The Gods: Let it be known that the Aztec pantheon had over 400 gods. I'll only include the ones Tecun interacted with.
Huitzilopochtli (weet-see-low-POACH-tlee), The Aztec god of war. Usually associated with the Eagle and the Hummingbird. A few facts is that the infamous heart-ripping ceremonies were for him. And the very first thing he did as a newborn god was kill his 400 older siblings. The Aztec equivalent to Ares.

Tezcatlipoca (tess-kawt-lee-POKE-ah), The god of rulers, sorcerers and warriors; night, death, discord, conflict, temptation and change and slaves. The Aztec equivalent of Hades almost. Usually appearing in the form of a jaguar. In this guise, he was called Tepeyollotl (teh-peh-yo-LOT-ull) and his roar was believed to cause earthquakes and volcanic eruptions. One of the most important gods in Aztec be considered an equal to Hades.

Quetzalcoatl (kett-sal-coh-AWE-tull), the Plumed Serpent. God of wind, dawn, the morning star (aka Venus), knowledge, arts, and crafts, and one of the oldest gods. Usually fighting against Tezcatlipoca. The Aztec equivalent of Zeus.

Xochipilli, the Flower Prince, the god of art, games, beauty, dance, flowers, music, and song. His twin sister was Xochiquetzal. Depicted as a handsome youth.

Xochiquetzal, The goddess of the flowers, dancing, beauty, sex, crafts, fertility, dance, music, singing, weaving, magic, and love. Twin brother is Xochipilli. Depicted as an alluring and youthful woman. Her and her twin are equal to Aphrodite. Yes there are two of them.

Huracan, The Mayan God of wind, storm, fire and one of the creator deities who participated in all three attempts at creating humanity. Tecun's father and 'handler'. Usually seen as a one-legged man with a prosthetic leg. Since he is a god however he usually walks with two working legs should he present himself. The Mayan equivalent of Zeus.

Items, Places, and other Misc Things:

Obsidian, a black glasslike rock formed from volcanic activity, it has gained various mystical properties and superstitions surrounding it, the most prominent of which being its association with demons. The Aztecs used obsidian blades embedded in a wooden club to make a deadly weapon known as the Macuahuitl. The blades were easily sharp enough to decapitate a man, and can supposedly decapitate a horse if used correctly. (Unfortunately for the Aztecs, a glass blade, no matter how sharp, isn't durable enough to be much help against an enemy armored in steel. Unless its Divine obsidian made by gods.)

Mictlan was the underworld, or Hades, of Aztec mythology. Most people who died went to Mictlan, although other possibilities existed . Mictlan consisted of nine distinct levels. The journey from the first level to the ninth was difficult and took four years, but the dead were aided by the psychopomp, Xolotl. The dead had to pass many challenges, such as crossing a mountain range where the mountains crashed into each other, a field with wind that blew flesh-scraping knives, and a river of blood with fearsome jaguars. Mictlan is ruled by a king, Mictlantecuhtli and his wife, Mictecacihuatl.

Nagual (nah-wall), this was a person's "shadow self," a piece of a person's soul in animal form. Even the gods had these. Quetzalcoatl had Xolotl, the dog-headed god of fire who guided the dead to their resting place. Tecun has the ability to interact with his nagual Tenoch

Blood: Tecun always carries a self filling bottle of blood on his person and if it goes missing it will always reappear like Percy's Riptide. The blood is from the offerings to the Aztecs so many years ago and blood spilled on all Aztec and Mayan land. Because of Tecun's bodily change at the hands of the Night Axe he has an immune system capable of killing off any earthly disease, the ability to completely metabolize blood and the ability to heal by consuming it. Blood to the Aztecs is Ambrosia for the Greeks. The primary difference is that the blood poses no danger, unlike ambrosia which would kill a demigod if they consume too much, because of the fundamental difference between the two. This also had the side effect of a blood fetish and a risk of addiction. Despite all this it annoys when someone calls him a vampire or anything similar.